Electronic gaming machines (“EGMs”) offer players a variety of games such as slot games, video poker games, roulette games, keno games, lottery games like Powerball, and other types of wagering games that are commonly deployed at a casino, other gaming venues or at home on the internet. EGMs may be of many types, from traditional “slot machines” to networked computing devices that perform equivalent functionality using functions on the networked computing device interactively coordinated with functions on a host server. Some examples of networked computing devices include but are not limited to a personal computer, a smartphone, a tablet computer, or any computing device which can be integrated into another device, such as eyeglasses, automobiles, and others.
Play on the EGMs typically requires the player to place a wager on the outcome of a primary game. On many such EGMs, additional prizes in the form of progressive prizes or bonus prizes are also available that offer the player an opportunity to win a prize that is separate from the prize awarded for winning the base or primary game. A progressive game is one in which a prize has an increasing value as a function of the play on one or more EGMs and may be won by a player on one or more EGMs. In some cases, the player is eligible for a chance to win the progressive game or bonus game after qualifying for the progressive or bonus round. In other cases, the progressive game win is integrated into the base game. This chance to win is achieved by hitting a certain winning combination or event on or related to the base or primary game, although it may also be achieved based on another criteria such as the amount of play, elapsed time, number of games played, a random event or any other criteria set by the system. If the game is a progressive game, the player may have an opportunity to win extra game credits, game tokens or other awards, including but not limited to a very large cash prize that may be in the millions of dollars. Given the large lottery-style jackpots that have been seen in recent times by combining multiple states' games into combined large jackpot games, it is reasonable to project that progressive gaming prizes could grow by integration and have prizes rise to those same levels or exceed them. A billion dollar progressive is a realistic possibility in a large scale or worldwide network.
Progressive jackpots are well known in the art and are commonly funded by allocating a portion or portions of each bet on one or more EGMs into one or more progressive prizes that are incremented until they are won. The amount of the prize may be increased as a function of play, elapsed time, or another mechanism. An example of a prior art progressive system is disclosed in United States Patent Publication No. 2006/0142079A1 assigned to IGT® entitled “Universal Progressive Game Pool” which is incorporated by reference in its entirety herein.
EGMs are available in many different forms. One common form of EGM is a machine that is microprocessor based and individually generates random number numbers using a hardware or software random number generator (“RNG”) to provide random numbers that map to winning and losing outcomes for a particular game. These RNG-based EGMs are deployed in many legalized gaming jurisdictions throughout the United States and the rest of the world, including the state of Nevada. Many jurisdictions require that the probability of a win on any given play of the game is the same. RNG-based EGMs are regularly networked together in progressive systems in a single jurisdiction such as Nevada. Megabucks is one such system that is owned and operated by IGT® of Las Vegas, Nev. Such systems with progressive prizes have been operating for many years and it is not uncommon for the top prize to reach into the tens of millions of dollars.
A second common form of EGM is a machine that is microprocessor based, but that is connected to a network with other EGMs. The system includes a central server that generates and distributes game outcomes from a finite pool of outcomes. Each outcome specifies whether the player wins or loses, and how much the player is awarded in the case of a win. The probability of a win on any given play of the game changes with every play as the pool of outcomes is depleted. For each game played on any of the EGMs on the network, the game outcome is distributed to the individual EGMs that participate on a given game whose pools are on the central server. Like RNG-based EGMs, finite pool type EGMs are also deployed in a number of legalized gaming jurisdictions throughout the United States and the rest of the world, including tribal gaming in the state of Washington. An example of a finite pool system is disclosed in U.S. Pat. No. 7,775,875 assigned to IGT® entitled “Gaming Methods and System” which is incorporated by reference in its entirety herein.
A third form of EGM incorporates a networked computing device and a computer server. It may replicate functions of an RNG-based system or a finite pool based system. Such a system may be implemented as a client-server system in which the networked computing device client has functionality that displays gaming results generated by the server, which controls gaming and accounting functionality. The client device may be a personal computer, smartphone, tablet computer, entertainment gaming system like an XBOX® gaming system from MICROSOFT, wearable glasses like GOOGLE® GLASS device, or a processing element integrated into another device, such as an automobile or any other device which has the capability to support comparable functions.
A fourth type of EGM is a hybrid EGM which uses any of the aforementioned device configurations and combines elements of finite pool based EGMs and RNG based EGMs. Finite pool systems can be configured in many ways, depending on:                (a) The type of wagering games with which they are being used (e.g. various slot game themes, keno, etc.);        (b) Restrictions placed by jurisdictional regulations; and        (c) Technological capabilities and preferences of the manufacturer of the system.        
Variations in pools can be by the size of the pools, number of pools open at one time, and the content of each pool element. In some jurisdictions (e.g. charitable gaming in Minnesota), finite pools are used in electronic implementations of pull-tab systems. In those systems, pool sizes are limited to 7500 elements. In other applications (e.g. Washington state tribal gaming, which is based on electronic implementations of lottery scratch tickets) pools sizes may be many millions. In some systems the pool sizes could be billions, or even higher. The content of each element of a finite pool (also called a game set) is the result of a single wager. That content may include, but is not limited to, a specification of win or loss, an amount of the prize, a graphic representation of the result of a play, a coded representation of the graphic result of a play, a unique identification for the play element, or a combination of those elements.
Finite pools may be used in conjunction with EGMs which simulate the play of casino slot machines (although they can be used with other wagering game types, including keno, bingo, pull-tabs, card games and others). One objective of the finite pool is to have a predetermined set of player results in terms of winning amounts. In such a game the player typically has the choice of the amount to bet on each play. One finite pool is generally required for each play denomination to have a deterministic amount of the prizes played and prizes won in each play denomination.
One or more EGMs may place wagers and retrieve results from a prize pool. As a pool is completely exhausted, a new pool is opened which allows play to continue. This is preferably an automated process transparent to the player. In a modified implementation, multiple pools are overlapped as one or more pools are depleted.
A group of RNG-based EGMs or a group of finite pool based EGMs may be connected to a progressive system or other bonus system that offers players the opportunity to win a bonus prize such as a progressive prize. The experience of operators and manufacturers of EGMs is that larger prizes, particularly progressives that grow over time, attract players. The larger the prize, the more players are attracted to it. The same phenomenon occurs with a large fixed prize, but the appeal seems even greater with a progressive prize that is continually building attracting more and more players as it grows. Accordingly, in traditional RNG-based EGM gaming venues, wide area progressive (“WAP”) systems have been established to link various gaming machines in different gaming venues (like casinos) to create a pooled prize with an incrementing prize value that may be in the millions or tens of millions of dollars.
One of the most successful large-scale networked bonus prize games that is in the form of a progressive, is Megabucks®, which was established in 1986 by IGT® of Las Vegas, Nev. While linked systems offering large prizes such as progressives have been in place for several years, they were principally limited to networks of EGMs within a single gaming establishment. Megabucks® established the concept of a prize that grew progressively larger as a portion of every wager was added to a fund that funded the jackpot prize for EGMs linked across multiple gaming establishments within a jurisdiction. The increasing prize value was displayed in real-time on a display over the EGMs connected to the Megabucks® WAP system.
The high prize values and the compelling display signage were popular with players, and Megabucks® became a standard offering in most casinos in Nevada. Soon Megabucks® was offered in other gaming jurisdictions and new wide area progressive game systems were offered by IGT® and other manufacturers. In the future it is anticipated that the size and scope of large-scale, networked bonus systems will increase significantly as the operators of these systems and regulators in different jurisdictions around the country and world come together to integrate more EGMs into larger and larger networks to offer much larger prizes and increase public interest and revenue. These large scale systems may be configured to provide large awards in the form of progressive jackpots or fixed jackpots.
In operation, the larger the jackpots, the more public interest is garnered and the more play results. It follows that the more EGMs and the more casinos that are linked together in these systems, the higher the prizes can be and the more successful the systems will be in generating revenues for the operators.
Accordingly, there is increasing interest in having large-scale networked bonus systems that cross jurisdictional boundaries. However, the linking of player devices in RNG-based gaming jurisdictions and those in finite pool based jurisdictions has not been implemented for three reasons:                (a) Many jurisdictions have legal prohibitions preventing linking games across jurisdictional boundaries;        (b) Finite Pools are limited in size and may not be able to support the very low probabilities of a jackpot win that are required of each machine in a large-scale networked bonus system; and        (c) The mathematical differences between RNG based gaming systems and finite pool based gaming systems raise questions as to whether all players across a network will have equal opportunities to win on any given play.        
In view of the limitations described above, the operation of a particular linked system has been typically limited to EGMs within the physical boundaries of a particular legalized gaming jurisdiction or a grouping of casinos (e.g. interstate networks of tribal gaming casinos). Such systems have been limited exclusively to either all RNG-based EGMs or all finite pool based EGMs. In a linked system with either type of EGM, the amount of the prize offered is often funded by a portion of the wagers placed on EGMs in the system, and the prizes are awarded depending on any number of possible criteria including an outcome of the base game determined by the RNG on an RNG-based EGM, or alternatively in the case of a linked system with finite pool based EGMs connected to it, the game outcome of the base game determined by the RNG of the central server that delivers game outcomes to the EGMs. It is also possible that the funding of the big prize may be as a portion of prizes won or another formula. Alternatively, for either an RNG-based or finite pool based network of EGMs, linked prizes on linked systems may be awarded based on a coin-in value, number of plays or other criteria set by the system.
As discussed above, a connection of mixed groupings of RNG-based EGMs and finite pool based EGMs together on single linked system has never been done. This is because the two different types of EGMs operate in a fundamentally different manner limiting the ability to offer to all players an equal probability of winning a common jackpot prize to any given RNG-based EGM or finite pool based EGM connected to the same linked system. An underlying principle of a gaming system with RNG based EGMs is that the probability of winning any prize is the same on every play. On the other hand, the probability of winning any prize on a finite pool based gaming system changes on every play as the pool from which the plays are chosen is depleted. As a consequence, players in a gaming system with RNG based EGMs and players in a gaming system with finite-pool based EGMs will generally not have equal opportunities to win the jackpot at any given point in time. Details of the degree of difference will depend on many of the particulars of the finite-pool implementations (e.g. sizes of pools). Any inequity will raise questions of the fairness and integrity of the system which impact the viability of the system as a whole.
As an example, assume that there are three gaming venues A, B and C with EGMs participating in a linked game network, Venues A and B have finite pool based EGMs and venue C has RNG based EGMs. At the start of play, T1, all three have nominally the same percentage chance overall of achieving a win of the linked prize on the first play. But at a later time, T2, after a number of plays and where venue A has experienced a number of jackpot hits from its finite pools since T1, the percentage chance of achieving a win of the linked prize at venue A is reduced for the next play. In venue B at time T2, where no jackpot winners have been selected from the open pools since T1, the percentage chance of achieving a win of the linked prize is increased for the next play. The result is that during a time of a high jackpot interest, the players at the three venues have different probabilities of winning the prize at any given point in time. Players at venue B have the best chance, players at venue A have the worst chance, and players at venue C have a likelihood of winning that is somewhere in between the chances at venue A and venue B.
There is a need for a solution that will enable finite-pool based gaming systems to operate on the same jackpot system with RNG based EGMs and allow all players to have statistically equal chances of winning prizes at all points in time.
The present invention is directed to large-scale linked bonus gaming systems, including but not limited to systems that offer progressive jackpots or large fixed prizes, and methods that combine RNG-based EGMs with hybrid finite pool based EGMs. A hybrid finite pool based EGM is one that includes a randomizing element offering players utilizing either type of EGM an equal opportunity of winning a common jackpot. The result is a linked system that is mathematically equitable to all parties and preserves principles of fairness.